PREFACE. 
THE papers contained in this little volume are reprinted from 
the New Puytocoaist, Vols. X and XI, 1911-12, in order to form a 
permanent record of the first international phytogeographical 
excursion which has been organised independently of any congress 
or other meeting, with the single intention of affording opportunity 
for joint observation and discussion between phytogeographers of 
different nations. 
The editor was fortunate in obtaining a contribution from 
every member of the international party, and the collected papers 
form a distinctly valuable body of information and opinion, 
The floristic side of the excursion occupies a good deal more 
space than was originally contemplated. This is due simply to the 
more advanced state of development of floristic as contrasted with 
ecological plant-geography, and the consequent greater ease of 
comparison between Continental and British species and varieties, 
than between Continental and British plant-communities. 
On the purely vegetational side, however, there is no doubt 
from their published remarks that the leading Continental plant- 
geographers have learned a great deal from this rapid survey 
of British vegetation, nor can it be questioned that British 
ecologists are profiting from their foreign colleagues’ impressions of 
British ecological conditions and criticisms of British synecological 
conceptions. 
With regard to these last it has appeared to the present writer 
premature to attempt either a revision or a defence of British 
synecological concepts and nomenclature. The general relations of 
British vegetation to that of Central Europe are admirably and 
most instructively dealt with in the papers of Professor Drude 
and of Professor Schröter. 
For these reasons no summary of the ecological, as opposed to 
the floristic, results of the Excursion appears in the present volume, 
But that these results will be exceedingly fruitful in leading to 
clearer understanding and eventually to universally acceptable 
concepts may be confidently asserted. The magnificent American 
tour arranged by Professors Clements and Cowles for the coming 
summer may be expected to bring us yet nearer to our common 
goal. 
It only remains for the present writer to thank in the most 
cordial way all the contributors to this record, and to express his 
unalloyed satisfaction with the results, from every standpoint, of the 
Excursion—results which far more than repay the effort devoted 
to it. 
GRANTCHESTER, A. G. TANSLEY, 
CAMBRIDGE, 
February, 1913. 
